Increased blood and red cell lead has been shown by te investigators to occur in glucose-6-phosphate dehydrogenase deficient school age blacks independently of the increased red cell lead in iron deficiency anemia is associated with a marked increase in tissue lead. The fact that preschool black children, as surveyed by the Bureau of Community and Environmental Management, have higher blood leads thant heir non-black peer groups in comparable housing, is provocative evidence for the possibility of enhanced absorption or altered metabolism of lead in the presence of genetic or acquired deficiencies of the red cell. The study is proposed in investigate the existence of racial differences in blood/red cell lead as well as the effects of G-6- PD deficiency, sickle cell trait, and iron deficiency anemia in 200 preschool and school children. These children all live in comparable housing and attend the same schools in central Omaha, an area we have previously idenitfied as high in atmospheric lead, and have previously been surveyed for the incidence of G-6-PD deficiency, sickle cell trait and anemia. Analysis will be made of the blood lead, red cell and serum lead, red cell ALA dehydratase, CBC, red cell indices, haptoglobins, 2,3, DPG and serum phosphate in the four following groups, each numbering at least 75 children: white control; black control; black, G-6-PD deficient; black Hgb S/A; with an anitcipated incdence of iron deficiency anemia in 10-20% of each group.